Method for making dutched cocoa

ABSTRACT

A method for making dutched cocoa involves first removing a considerable portion of the fat from a cocoa mass to form a reduced fat cocoa mass with less than 8 % fat by weight, then alkalizing the reduced fat cocoa to form dutched cocoa. With this sequence of steps, the formation of soaps is minimized because the soaps are formed by a reaction between the the alkalizing agents and cocoa fat. Thus, the taste of cocoa powder is improved, as well as its flowability, especially when the cocoa undergoes harsh alkalizing conditions, as is required for applications requiring very dark cocoa.

FIELD OF THE INVENTION

The present invention pertains to the production of dutched cocoa.

BACKGROUND OF THE INVENTION

In the manufacture of cocoa, it is often desirable to form “dutchedcocoa” for many food applications. Dutched cocoa has unique flavorcharacteristics and a darker, or even blackened, appearance as opposedto cocoa which has not been dutched. Dutching (also known as“alkalizing”) is accomplished in a well known manner by contacting cocoamass with an alkalizing agent, typically in the form of an aqueoussolution. Such alkalizing agents include potassium hydroxide, potassiumcarbonate, sodium hydroxide, sodium carbonate, sodium bicarbonate,ammonium bicarbonate, ammonium hydroxide, or mixtures thereof, forexample. The FDA has strict rules governing both the approved alkalizingagents and the maximum levels of usage of the alkalizing agents orcombinations thereof.

More specifically, dutching is typically done to cocoa bean kernels, ornibs, as well as to cocoa powder, or pieces of presscake, which arefirst reduced in particle size to less than ¼ inch, and more commonly toless than ⅛ inch diameter. The cocoa is then mixed with an aqueoussolution of one or more of the approved alkalizing agents in a knownmanner. This mixture is then usually heated in a vessel while mixing.For reddish colored cocoas, air is usually introduced into the mixerduring this reaction phase. For the production of black cocoas, theintroduction of air is minimized. The cooking can be done underatmospheric conditions or under pressure followed by atmospheric or evenvacuum conditions to facilitate drying (i.e., removal of moisture). Oncethe alkalizing treatment is complete with respect to dutched nibs, theyare milled into a flowable mass and reduced in fat content through theuse of hydraulically operated presses, to produce dutched cocoapresscake. The dutched cocoa is usually milled to a fine particle size(typically to a specification of 99% through a 200 mesh screen).

One adverse effect caused by the dutching of cocoa is the formation ofsoap due to the interaction of the alkalizing agent and the fat (and/orfree fatty acids) present in the cocoa mass. Soap formation occurs to aneven greater extent as a result of extreme alkalizing conditions, whichare required for the formation of very dark, or black dutched, cocoa. Insum, although the primary issues in evaluating the quality of dutchedcocoa are flavor and color, one quantitative measurement is the amountof soap in the processed cocoa.

The flow characteristics of cocoa mass or processed cocoa are anotherimportant consideration in processing cocoa. In particular, it isdesirable to avoid developing a form of cocoa which tends to stickeasily to processing equipment. This can cause delays in processing,difficulty in grinding to desired fineness, and possibly damage to plantequipment. Often, cocoa which has been dutched tends to. be more likelyto exhibit these types of adverse flow characteristics.

SUMMARY OF THE INVENTION

The present invention provides a method for making dutched cocoacomprising the steps of first removing fat from a cocoa mass to form areduced fat cocoa mass and then alkalizing the reduced fat cocoa to formdutched cocoa. The step of removing fat is carried out to an extent suchthat the reduced fat cocoa mass has a fat content of less than 8% byweight. This order of processing tends to minimize soap formation,improve taste, and result in processed cocoa having improved handlingcharacteristics than cocoa which is dutched first. The inventionproduces the most effective and valuable results when applied to moreextreme alkalizing conditions, such as those used for the manufacture ofvery dark or black dutched cocoa powders.

An objective is to produce a higher quality dutched cocoa powder thancan be manufactured by conventional methods, when starting with normalfat content cocoa presscakes or powders (typically 10-12% cocoa buttercontent). In sum, the steps of the process of an embodiment of theinvention include first reducing the fat content of the cocoa from thatwhich is usually available from conventional hydraulic pressing of cocoapowder or presscake (10-12% fat), alkalizing the lowfat cocoa, and,optionally, the reintroduction of cocoa butter and/or other fats to“reconstitute” the cocoa. The critical operation is the removal of aconsiderable portion of the cocoa butter prior to subjecting it to thedutching process.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary, but are notrestrictive, of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to a method for making dutched cocoa.The invention includes removing fat from a cocoa mass to form a reducedfat cocoa mass then alkalizing the reduced fat cocoa to form dutchedcocoa. As used herein, the term “cocoa mass” refers to a mixture ofcocoa fat and cocoa solids which has not yet been dutched. For example,cocoa mass includes cocoa liquor, which results from grinding cocoa nibsand typically has between 50-58% fat content. Cocoa mass also includescocoa presscake, which is the cake formed from a hydraulic or screwpress used to remove some fat from cocoa liquor, or cocoa powder, whichis milled or comminuted cocoa presscake. Cocoa presscake and cocoapowder often have a fat content of between 10 to 12%. Cocoa mass mayinclude any mixture of cocoa fat and solids, including one which has notyet had any fat removed, one which has undergone partial pressing (suchas between 20-50%) or one which has undergone full hydraulic or screwpressing such as one with a fat content of as low as about 8%. In sum,the term cocoa mass contemplates a non-dutched mixture having a fatcontent as high as that found in cocoa liquor to a fat content low butstill having a noticeable impact that, if dutched, would have anobservable (by taste) soap content.

Thus, the step of removing fat from a cocoa mass contemplates anycombination of known fat removal processes, such as by using a hydraulicpress, a screw press, or an extraction process, or combinations thereof.For example, when the cocoa mass is cocoa powder or cocoa presscake, thestep of removing fat may include extracting the fat by contacting thecocoa mass with a liquefied or supercritical solvent, and the methodalso involves separating the solvent from the reduced fat cocoa mass.Any known solvents may be used for this purpose, such as propane,butane, hexane, and carbon dioxide, among many others. There are manyknown processes in the art to effect this extraction, such as thosedescribed in U.S. Pat. No. 6,111,119, incorporated herein by reference.

Alternatively, although less preferable, the cocoa mass may be cocoaliquor, in which case the step of removing fat from the cocoa mass mayinclude first applying pressure in a press to remove a first portion ofsaid fat and extracting a second portion of the fat by contacting thecocoa mass with a liquefied or supercritical solvent as discussed above,in which case the method also includes separating the solvent from thereduced fat cocoa mass. Alternatively, the step of removing fat mayinclude extracting fat from the cocoa liquor solely by contacting thecocoa liquor with a liquefied or supercritical solvent, thus avoidingthe need for a hydraulic or screw press.

As mentioned above, the present invention contemplates first removingfat from a cocoa mass then alkalizing the reduced fat cocoa to formdutched cocoa. The extent to which the fat is removed need not besubstantially all of the fat present in the cocoa mass, but only thatamount such that subsequent dutching of the reduced fat cocoa mass doesnot result in the formation of an appreciable or noticeable amount ofsoap. The upper limit of the fat content of the reduced fat cocoa masswill depend on the end use of the processed cocoa and the extent towhich dutching is needed. For example, when the use of the cocoarequires a very dark cocoa, thus requiring extreme dutching conditions,soap formation will occur more readily and to a greater extent. In thiscase, a relatively lower initial fat content in the reduced fat cocoamass would be needed. In many cases, a fat content of about 8 % byweight should be sufficient to achieve processed cocoa which has areduced amount of soap, and thus improved flavor, color, and/or flowcharacteristics than processed cocoa which undergoes dutching at ahigher fat content. More preferably, the step of removing fat iscontinued until a reduced fat cocoa mass having a fat content of lessthan 4% by weight is achieved and, still more preferably, less than 1%fat by weight is achieved.

The step of dutching or alkalizing the reduced fat cocoa mass may becarried out in any manner known in the art. As mentioned above,alkalizing the reduced fat cocoa mass typically involves contacting thereduced fat cocoa mass with an aqueous solution of an alkalizing agentselected from the group consisting or potassium hydroxide, potassiumcarbonate, sodium hydroxide, sodium carbonate, sodium bicarbonate,ammonium bicarbonate, ammonium hydroxide, or mixtures thereof. Thespecific alkalizing conditions are not critical to achieve the purposesof the present invention but are dictated more so by the desired end usefor the cocoa being processed.

Dutching with reduced fat cocoa mass requires certain equipmentconsiderations, especially when the fat content is less than 1%. Morestringent dust control measures must be taken, specifically within thedutching reactor to contain fine cocoa particles from escaping withwater vapor/steam during the drying cycle. Special high temperaturefilter bags or cartridges are commercially available for installation ina raised dome on top of the reactor. When producing very dark cocoasespecially black, high viscosities are reached due to the large quantityof water used in the formula. The use of lower fat cocoas results ineven higher viscosities. This requires even more ruggedly designedagitation or reduced batch size. Also in the production of black cocoausing lower fat cocoas, considerably harder particles are formed, thusrequiring more intense grinding, or milling.

With this process, two products are developed: Cocoa butter and dutchedcocoa powder. In one embodiment of the present invention, the dutchedcocoa powder may be sold as low-fat dutched cocoa powder. According toan alternative embodiment, fat is added back to the defatted cocoapowder after the dutching process. The type of fat, if any, added to thedefatted dutched cocoa could be cocoa butter or could be any other typeof fat, or blends of fats if desired. Of course, if fats other thancocoa butter are added, this would change the labeling requirements forthe product. This can be done in the same vessel or after transfer, inanother vessel specifically for that purpose. The amount of cocoa butteradded can vary from none up to any amount desired to produce a dutchedcocoa powder with the requisite fat content. Typically, dutched cocoasare available with fat contents (i.e., cocoa butter) of less than 1% upto 24%.

In sum, the present invention recognizes that the treatment of typicalcocoa material with alkalizing agents and water tends to develop uniquecolor and flavor but also results in the saponification of a portion ofthe cocoa butter. The invention calls for first removing most of thecocoa butter from the cocoa, to less than 8%, for example, and morepreferably to less than 4% and most preferably to less than 1%. Afterthe reduction of fat, then the normal process for dutching is done.Dutching preferably occurs when the fat content of the cocoa mass is atits lowest point during processing thereof.

Removal of fat prior to dutching reduces the amount of fat (cocoabutter) subjected to the aqueous alkali solution under conditions whichcan saponify a portion of the cocoa butter. Reducing the amount of fatin the cocoa prior to dutching limits the amount of soap which can begenerated during the alkalizing process. This is of special interestwith regard to the highly alkalized cocoas (e.g., black cocoa). Whetherthe cocoa butter is added back after alkalizing of the lowfat cocoa orif the product is maintained as a lowfat product, the reduction of soap(especially with regard to highly alkalized cocoas) results in a productwith superior flow characteristics, resulting in easier milling, and ina product with a flavor which is improved and considered to be of highercommercial value.

EXAMPLE

The following example is included to more clearly demonstrate theoverall nature of the invention. This invention is exemplary, notrestrictive, of the invention.

A batch of cocoa presscake (cocoa powder having between 10/12% fat byweight) was obtained from a first commercial source and the fat wasextracted using propane to less than 1% fat in a manner consistent withU.S. Pat. No. 6,111,119. After desolventizing, an aqueous solution ofammonium bicarbonate was added in a first dose to the sample and anaqueous solution of sodium hydroxide was added in a second dose to thesample. The mixture was then cooked by being heated to above 230° F.,pressure cooked for between 2 to 4 hours, then dried under atmosphericconditions for 4 hours and then finally vacuum dried for between 3 and 4hours. The total cycle time for the defatting and alkalizing approached16 hours.

The product was then milled in a pin mill with an air classifier to afineness of 99.5% through a 200 mesh screen. The product was then usedin a formula to make a wafer sample. The same formula was used to makethree additional comparative wafer samples but, in place of thedefatted, dutch cocoa of the present invention, the following was used:(1) cocoa powder from a dutched (or alkalized) cocoa presscake from thefirst source; (2) cocoa powder from a dutched cocoa presscake from asecond commercial source; and (3) cocoa powder from presscake from adutched dehulled cocoa bean (i.e., nib). As each of comparative exampleshad a cocoa fat content of between 10/12%, the remainder of the fatcontent called for by the wafer was made up by the addition of vegetablefat for the wafer of the present invention.

Using a blind taste panel of laypersons, the wafer produced using thedefatted dutched cocoa of the present invention was found to becomparable in taste to the wafer produced using the cocoa of comparativeexample (3). Both the wafer produced from the defatted dutched cocoa ofthe present invention and from the cocoa of comparative example (3) werefound to be superior to the wafers produced from comparative examples(1) and (2). It should be noted that dutched cocoa produced from the nibis considered superior in taste to dutched cocoa produced from presscakein that about 90% of the soap produced in the alkalization process isremoved during the pressing following the alkalization of the dehulledcocoa bean.

Although illustrated and described herein with reference to certainspecific embodiments and examples, the present invention is neverthelessnot intended to be limited to the details shown. Rather, the claimsshould be read to include various modifications within the scope andrange of equivalents of the claims, without departing from the spirit ofthe invention.

1. A method for making dutched cocoa comprising the steps of: removingfat from a cocoa mass to form a reduced fat cocoa mass having less than8 % fat by weight; and alkalizing said reduced fat cocoa mass to formdutched cocoa.
 2. The method in accordance with claim 1, wherein saidcocoa mass comprises cocoa powder or cocoa presscake and the step ofremoving said fat comprises extracting said fat by contacting said cocoamass with a liquefied or supercritical solvent, wherein said methodfurther comprises separating said solvent from said reduced fat cocoamass.
 3. The method in accordance with claim 2, wherein said solvent ispropane or butane or a mixture thereof.
 4. The method in accordance withclaim 2, wherein said cocoa powder or cocoa presscake comprises betweenabout 10 to 12% fat by weight.
 5. The method in accordance with claim 1,wherein said reduced fat cocoa mass comprises less than 4% fat byweight.
 6. The method in accordance with claim 5, wherein said reducedfat cocoa mass comprises less than 1% fat by weight.
 7. The method inaccordance with claim 1, wherein said cocoa mass is cocoa liquor.
 8. Themethod in accordance with claim 7, wherein said cocoa liquor comprisesabout 50-58% fat by weight.
 9. The method in accordance with claim 7,wherein the step of removing said fat comprises applying pressure in apress to remove a first portion of said fat and extracting a secondportion of said fat by contacting said cocoa mass with a liquefied orsupercritical solvent, wherein said method further comprises separatingsaid solvent from said reduced fat cocoa mass.
 10. The method inaccordance with claim 7, wherein the step of removing said fiatcomprises extracting said fat by contacting said cocoa mass with aliquefied or supercritical solvent, wherein said method furthercomprises separating said solvent from said reduced fat cocoa mass. 11.The method in accordance with claim 1, wherein the step of alkalizingsaid reduced fat cocoa mass comprises contacting said reduced fat cocoamass with an aqueous solution of al alkalizing agent selected from thegroup consisting or potassium hydroxide, potassium carbonate, sodiumhydroxide, sodium carbonate, sodium bicarbonate, ammonium bicarbonate,ammonium hydroxide, or mixtures thereof.
 12. The method in accordancewith claim 1 further comprising adding fat to said dutched cocoa to forma reconstituted product.
 13. The method in accordance with claim 12,wherein said fat is cocoa fat.
 14. The product formed by any processaccording to claims 1-13.